| Atmospheric temperature and humidity profiles are the important parameters of the atmospheric environment, which have important applications in weather forecasting and atmospheric sciences. Atmospheric temperature and humidity profile measurements and retrievals by multi-channel ground based microwave sounders are investigated. This thesis has four parts:1. The atmospheric millimeter-wave propagation model and microwave radiative transfer model are introduced, and the retrieval methods of atmospheric temperature and humidity profiles are introduced, especially the statistical regression and the neural network methods, which are internationally widely used.2. The convergence behaviors of the statistical regression and the artificial neural network based retrieval methods are analyzed. The results show that both methods can have very meaningful and accurate results for retrieval of atmospheric temperature and humidity profiles. Especially, the results are more accurate for retrievals of lower atmosphere.3. Based on the retrieval model, impacts of key systems parameters of a microwave radiometer on the measurement and retrieval performances, such as the beam width and main beam efficiency of receiving antenna, the brightness temperature measurement precisions and calibration accuracies, are investigated. Performances of two ground-based microwave sounders, the RPG-HATPRO and MP-3000A, are compared. 4. The selection of temperature sounding channels and humidity sounding channels is studied. Firstly, channel combination with fixed number of channels is optimized. Secondly, by comparing the inversion results with different number of channels, the channel combination with different channel numbers is optimized and finally determined for atmospheric temperature and humidity profile retrieval.The result of this thesis can provide meaningful references to the design of ground-based multi-channel microwave radiometer for atmospheric temperature and humidity profiles.
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